Manufacture of silicon carbid.



NITED STATES PATENT OFFICE.

FRANK .1, Tom, on NIAGARA FALLS, NEW Yank, AssIeNon To run c nnonUNnUir 1,013,701. No Drawing.

According to the well known method of manufacture of silicon carbid, a mixture of pulverized coke, sand, salt and sawdust, is

subjected to great heat in an electric furnace. The resulting product is a loose aggregation of crystals of various sizeswith a considerable proportion of interstices in .the crystal mass.

I have discovered that by placing porous masses of silicon carbid in or in contact with silicon and heating the masses to the temperature. required for the formation of silicon carbid the silicon will penetrate the pores of the mass,- compact it, and cement 1t into a dense form consisting of silicon carbid and free silicon. I have found that aggregations of silicon carbid crystals may be converted into-a dense form of silicon 'oarbid by submitting them to the action of vapors of silicon and causing the silicon to penetrate the pores of the or stalline mass and there condense and com ine with the silicon carbid;

. In the practice of my invention care should be. taken not to carry the temperature to a point sufliciently high' to decomose the resulting product and convert it into graphite.

The subject-matter-of this application is analogous to that of my Patent 913,324, February23, 1909. n A

Specification of Letters Iatent.

Application filed July 10, 1908. Serial No. 442,902.

posited in the comrANY, or NIAGARA rALLs, NEW max, A conronArroN or rnNNsnvANIA V MANUFACTURE or sILIcoN 'cAnnm. J

I claimE- 'l 1. The 'process of making dense silicon carbid whlch consists in heating silicon car-v bid in proximity to silicon and allowing the silicon to penetrate the; pores of the silicon carbid and cement it together.

2. The recess of making dense silicon carbid which consists in heating orous aggregations of silicon carbid crysta s in prox-' imity to vapors of silicon, and causing the silicon to penetrate and condense in 'the pores of the crystalline silicon carbid mass.

3. The process of making dense silicon carbid whlch consists in causing free silicon toform in a disseminated state a silicon carbid mass.

.4. As a new article of manufacture, a shaped piece of silicon carbid of great density and compactness and having silicon depores thereof; substantially throughout as described. p

5. As a new article of manufacture, silicon carbid of great density and compactness and having silicon deposited in the pores thereof; substantially asdescribed.

6. As a new article of manufacture, dense compacted silicon carbid consisting of silicon carbid crystals cemented together by silicon; substantially as described. a newarticle of manufacture, a form containing silicon carbid and silicon; substantially as described.

In testimony whereof, I havehereunto set my hand.

FRANK J. TONE.

Witnesses:

AsHMnAn G. Romans, EDMUND S. SMITH.

I atented Jan. 2,1912. 

